| (19) |
 |
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(11) |
EP 0 369 328 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
06.02.1991 Bulletin 1991/06 |
| (43) |
Date of publication A2: |
|
23.05.1990 Bulletin 1990/21 |
| (22) |
Date of filing: 09.11.1989 |
|
| (51) |
International Patent Classification (IPC)5: D21H 17/74
// D21H17/14, D21H17/17, D21H17/23, D21H17/29, D21H17/66 |
|
| (84) |
Designated Contracting States: |
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AT BE DE ES FR GB IT SE |
| (30) |
Priority: |
10.11.1988 US 270338
|
| (71) |
Applicant: HERCULES INCORPORATED |
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Wilmington
Delaware 19894 (US) |
|
| (72) |
Inventors: |
|
- Edwards Derek Wayne
Wilmington, DE 19802 (US)
- Townsend David Francis
Hockessin, DE 19707 (US)
|
| (74) |
Representative: Lederer, Franz, Dr. et al |
|
Lederer, Keller & Riederer
Patentanwälte
Prinzregentenstrasse 16
80538 München
80538 München (DE) |
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| |
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| (54) |
Alkyl ketene dimer dispersion |
(57) Stabilized dispersions of alkyl ketene dimer paper sizing agents that comprise up
to about 30% by weight of ketene dimer, a water soluble cationic starch, and a lignin
sulfonate, and also contain about 0.15 to about 1.5% of aluminum sulfate and from
about 0.1 to about 5% of a carboxylic acid having from 1 to 10 carbon atoms, a pKa
of up to about 5 and a solubility of at least about 0.1 parts in 100 parts of water
(the percentages being based upon the weight of the dimer), are disclosed.